/*
* Copyright (C) 2005, 2006, 2007, 2008, 2010 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#ifndef RetainPtr_h
#define RetainPtr_h
#include "HashTraits.h"
#include "NullPtr.h"
#include "TypeTraits.h"
#include <algorithm>
#if USE(CF)
#include <CoreFoundation/CoreFoundation.h>
#endif
#ifdef __OBJC__
#import <Foundation/Foundation.h>
#endif
namespace WTF {
// Unlike most most of our smart pointers, RetainPtr can take either the pointer type or the pointed-to type,
// so both RetainPtr<NSDictionary> and RetainPtr<CFDictionaryRef> will work.
enum AdoptCFTag { AdoptCF };
enum AdoptNSTag { AdoptNS };
#ifdef __OBJC__
inline void adoptNSReference(id ptr)
{
if (ptr) {
CFRetain(ptr);
[ptr release];
}
}
#endif
template<typename T> class RetainPtr {
public:
typedef typename RemovePointer<T>::Type ValueType;
typedef ValueType* PtrType;
RetainPtr() : m_ptr(0) {}
RetainPtr(PtrType ptr) : m_ptr(ptr) { if (ptr) CFRetain(ptr); }
RetainPtr(AdoptCFTag, PtrType ptr) : m_ptr(ptr) { }
RetainPtr(AdoptNSTag, PtrType ptr) : m_ptr(ptr) { adoptNSReference(ptr); }
RetainPtr(const RetainPtr& o) : m_ptr(o.m_ptr) { if (PtrType ptr = m_ptr) CFRetain(ptr); }
// Hash table deleted values, which are only constructed and never copied or destroyed.
RetainPtr(HashTableDeletedValueType) : m_ptr(hashTableDeletedValue()) { }
bool isHashTableDeletedValue() const { return m_ptr == hashTableDeletedValue(); }
~RetainPtr() { if (PtrType ptr = m_ptr) CFRelease(ptr); }
template<typename U> RetainPtr(const RetainPtr<U>&);
PtrType get() const { return m_ptr; }
void clear();
PtrType leakRef() WARN_UNUSED_RETURN;
PtrType operator->() const { return m_ptr; }
bool operator!() const { return !m_ptr; }
// This conversion operator allows implicit conversion to bool but not to other integer types.
typedef PtrType RetainPtr::*UnspecifiedBoolType;
operator UnspecifiedBoolType() const { return m_ptr ? &RetainPtr::m_ptr : 0; }
RetainPtr& operator=(const RetainPtr&);
template<typename U> RetainPtr& operator=(const RetainPtr<U>&);
RetainPtr& operator=(PtrType);
template<typename U> RetainPtr& operator=(U*);
#if !HAVE(NULLPTR)
RetainPtr& operator=(std::nullptr_t) { clear(); return *this; }
#endif
void adoptCF(PtrType);
void adoptNS(PtrType);
void swap(RetainPtr&);
// FIXME: Remove releaseRef once we change all callers to call leakRef instead.
PtrType releaseRef() { return leakRef(); }
private:
static T* hashTableDeletedValue() { return reinterpret_cast<T*>(-1); }
PtrType m_ptr;
};
template<typename T> template<typename U> inline RetainPtr<T>::RetainPtr(const RetainPtr<U>& o)
: m_ptr(o.get())
{
if (PtrType ptr = m_ptr)
CFRetain(ptr);
}
template<typename T> inline void RetainPtr<T>::clear()
{
if (PtrType ptr = m_ptr) {
m_ptr = 0;
CFRelease(ptr);
}
}
template<typename T> inline typename RetainPtr<T>::PtrType RetainPtr<T>::leakRef()
{
PtrType ptr = m_ptr;
m_ptr = 0;
return ptr;
}
template<typename T> inline RetainPtr<T>& RetainPtr<T>::operator=(const RetainPtr<T>& o)
{
PtrType optr = o.get();
if (optr)
CFRetain(optr);
PtrType ptr = m_ptr;
m_ptr = optr;
if (ptr)
CFRelease(ptr);
return *this;
}
template<typename T> template<typename U> inline RetainPtr<T>& RetainPtr<T>::operator=(const RetainPtr<U>& o)
{
PtrType optr = o.get();
if (optr)
CFRetain(optr);
PtrType ptr = m_ptr;
m_ptr = optr;
if (ptr)
CFRelease(ptr);
return *this;
}
template<typename T> inline RetainPtr<T>& RetainPtr<T>::operator=(PtrType optr)
{
if (optr)
CFRetain(optr);
PtrType ptr = m_ptr;
m_ptr = optr;
if (ptr)
CFRelease(ptr);
return *this;
}
template<typename T> inline void RetainPtr<T>::adoptCF(PtrType optr)
{
PtrType ptr = m_ptr;
m_ptr = optr;
if (ptr)
CFRelease(ptr);
}
template<typename T> inline void RetainPtr<T>::adoptNS(PtrType optr)
{
adoptNSReference(optr);
PtrType ptr = m_ptr;
m_ptr = optr;
if (ptr)
CFRelease(ptr);
}
template<typename T> template<typename U> inline RetainPtr<T>& RetainPtr<T>::operator=(U* optr)
{
if (optr)
CFRetain(optr);
PtrType ptr = m_ptr;
m_ptr = optr;
if (ptr)
CFRelease(ptr);
return *this;
}
template<typename T> inline void RetainPtr<T>::swap(RetainPtr<T>& o)
{
std::swap(m_ptr, o.m_ptr);
}
template<typename T> inline void swap(RetainPtr<T>& a, RetainPtr<T>& b)
{
a.swap(b);
}
template<typename T, typename U> inline bool operator==(const RetainPtr<T>& a, const RetainPtr<U>& b)
{
return a.get() == b.get();
}
template<typename T, typename U> inline bool operator==(const RetainPtr<T>& a, U* b)
{
return a.get() == b;
}
template<typename T, typename U> inline bool operator==(T* a, const RetainPtr<U>& b)
{
return a == b.get();
}
template<typename T, typename U> inline bool operator!=(const RetainPtr<T>& a, const RetainPtr<U>& b)
{
return a.get() != b.get();
}
template<typename T, typename U> inline bool operator!=(const RetainPtr<T>& a, U* b)
{
return a.get() != b;
}
template<typename T, typename U> inline bool operator!=(T* a, const RetainPtr<U>& b)
{
return a != b.get();
}
template<typename P> struct HashTraits<RetainPtr<P> > : SimpleClassHashTraits<RetainPtr<P> > { };
template<typename P> struct PtrHash<RetainPtr<P> > : PtrHash<P*> {
using PtrHash<P*>::hash;
static unsigned hash(const RetainPtr<P>& key) { return hash(key.get()); }
using PtrHash<P*>::equal;
static bool equal(const RetainPtr<P>& a, const RetainPtr<P>& b) { return a == b; }
static bool equal(P* a, const RetainPtr<P>& b) { return a == b; }
static bool equal(const RetainPtr<P>& a, P* b) { return a == b; }
};
template<typename P> struct DefaultHash<RetainPtr<P> > { typedef PtrHash<RetainPtr<P> > Hash; };
} // namespace WTF
using WTF::AdoptCF;
using WTF::AdoptNS;
using WTF::RetainPtr;
#endif // WTF_RetainPtr_h